package PenTest.meituan.acm0406;

import java.util.Scanner;

public class acm1 {
    public static void main(String[] args){
        Scanner scanner = new Scanner(System.in);
        String s = scanner.nextLine();
        String target = "meituan";
        int count = 0;
        for (int i = 0; i < target.length(); i++) {
            if (target.charAt(i)!=s.charAt(i)) {
                count++;
            }
        }
        System.out.println(count);
    }

}
